Medicine and Health Sciences Commons^™

Re-Thinking The Summer Drenching Program, Brown Besier

Journal of the Department of Agriculture, Western Australia, Series 4

The summer drenching program has provided highly effective sheep worm control in Western Australia for many years - but recent research challenges its long term sustainability.

Trial results suggest that in large parts of the State, summer drenching is the main factor leading to the development of drench resistant worms. Alternative programs less likely to lead to drench resistance will require greater monitoring of worm burdens and panning pasture moves.

Virulent Footrot : Mild Or Severe?, Laurie Depiazzi

Journal of the Department of Agriculture, Western Australia, Series 4

The footrot eradication scheme in Western Australia has resulted in a low prevalence of severe footrot.

To appreciate the achievement, we need to understand what exactly is being eradicated. 'S' strains of Dichelorbacter nodosus, the infectious bacterium of footrot, are the target of footrot eradication. Laurie Depiazzi examines the basis for eradicating 'S' strains.

Lupin Stubbles : Getting The Best With Weaner Sheep, Keith Croker, Colin Mcdonald, Jeremy Allen

Journal of the Department of Agriculture, Western Australia, Series 4

Sweet lupins are now grown on about a million hectares in Western Australia each year. If half of the State's seven million weaners were grazed as recommended on half of the lupin stubbles, it could generate about $15 million from reduced supplementary feeding, greater wool production and other advantages. But correct management is important, particularly knowing when to take weaners out. Research by the Department over the last five years is now indicating how this should be done.

Quality Wool Production At Lower Cost, Peter Metcalfe

Journal of the Department of Agriculture, Western Australia, Series 4

Low wool prices are forcing farmers to reduce their sheep management costs but, fortunately, cost cutting is not resulting in lower wool production, poorer wool quality or lessened sheep care on the best wool growing properties.

Choosing Shower Dips For Sheep Lice, Tony Higgs, Bob Love

Journal of the Department of Agriculture, Western Australia, Series 4

The performance of all shower dip chemicals for sheep lice can vary depending on the active chemical and the conditions under which they are used.

Department of Agriculture trials have indicated that the wettable powders coumaphos and magnesium fluorosilicate were less effective at eradicating sheep lice than were synthetic pyrethroid and organophosphate dipping chemicals.

However, failure to eradicate sheep lice may be the result of several factors, many of them related to management.

Do Farmers Really Want To Eradicate Sheep Lice?, Chris Hawkins

Journal of the Department of Agriculture, Western Australia, Series 4

With the termination of Western Australia's Sheep Lice Eradication Campaign in 1993 farmers' views about the eradication of sheep lice are of greater relevance now than in the past. Lice control now rests with individual farmers and continuing local lice cell groups .

A recent survey of producers in the Moora Shire provides some key insights into farmers' thoughts about sheep lice and their eradication.

Progress Toward Eradication Of Virulent Footrot, Bob Mitchell

Journal of the Department of Agriculture, Western Australia, Series 4

Western Australia is well placed to eradicate virulent footrot from the State's sheep and goat populations.

Between 1950 and 1993 the proportion of sheep flocks with footrot fell from about 15 per cent to less than 2 percent, and the 1990-92 outbreak has been turned around. One hundred and eighty properties (]. 7 per cent) of flocks, mostly in the high rainfall South-West, are in quarantine for footrot today.

This high level of footrot control is the result of strong support from the sheep industry and years of good cooperation between farmers and the Department of Agriculture.

Western Australia leads …

New Technique Joins The Fight Against Footrot, Laurie Depiazzi, Mike Palmer, David Pitman

Journal of the Department of Agriculture, Western Australia, Series 4

The diagnosis of footrot in sheep and goats is not an easy task. Two main techniques are used for diagnosis - inspection of diseased feet on a farm and laboratory testing of bacteria isolated from foot scrapings. The interpretation of the results obtained by these methods requires a good understanding of the various forms of footrot.

A new laboratory technique has halved the time taken to detect those strains of the bacterium, Bacteroides (Dichelobacter) nodosus, that cause each form of the disease.

Phomopsis-Resistant Lupin Stubbles As Feed For Weaner Sheep, Colin Mcdonald, Keith Croker, Jeremy Allen

Journal of the Department of Agriculture, Western Australia, Series 4

The breeding of sweet, narrow-leafed lupins with increased resistance to Phomopsis leptostromiformis, the fungus that causes lupinosis in sheep, is a breakthrough for the summer nutrition of weaner sheep. The new resistant varieties, Gungurru for the medium (325 to 450 mm) rainfall areas and Yorrel for low rainfall areas (less than 325 mm), were released by the Department of Agriculture in 1988.

This article discusses progress in a four-year project which is examining liveweight and wool production of weaners grazing Gungurru stubbles.

Veterinary Consultancy Boosts Piggery Profits, Ashley Mercy

Journal of the Department of Agriculture, Western Australia, Series 4

A pilot Pig Herd Health Management Scheme co-ordinated by the Department of Agriculture has stimulated much increased involvement of veterinarians in the Western Australian pig industry. Co-ordinated by Ashley Mercy, principal veterinary officer (epidemiology) horn 1985 to 1989, the scheme demonstrated the value of having regular visits from veterinary consultants and in implementing programs to prevent disease and production problems occurring in herds.

The Incidence Of Lupinosis In Sheep Grazing Phomopsis-Resistant Lupin Stubbles, Peter Morcombe, Jeremy Allen

Journal of the Department of Agriculture, Western Australia, Series 4

Lupinosis is one of the major diseases of grazing livestock in Western Australia. It occurs when animals graze lupin stubble containing toxins produced by the fungus Phomopsis leptostromiformis. The Department of Agriculture has recently released new cultivars of Lupinus angustifolius which are more resistant to colonization by Phomopsis, and therefore develop less toxicity, than those previously available (Cowling et al. 1988). The new cultivars - Gungurru and Yorrel - are called Phomopsis-resistant, however their resistance is only moderate. The old cultivars are referred to as Phomopsis-susceptible.

The Live Sheep Export Industry, Richard Norris, Barry Richards, Tony Higgs

Journal of the Department of Agriculture, Western Australia, Series 4

Australia's live sheep trade to Middle Eastern countries is an important export industry. However, about 2 per cent of the sheep die, mainly during the sea voyage. The Western Australian Department of Agriculture has conducted a major research programme to improve the health and welfare of sheep during live export. The programme has'examined many aspects of the export sheep industry, and a substantial part of it has focused on why sheep die during sea transport.

Choosing A Calcium Supplement For Sheep Fed Cereal Grains, R L. Peet, Michael Hare

Journal of the Department of Agriculture, Western Australia, Series 4

Sheep fed cereal grains as an energy source over summer usually need added calcium because cereal grains are generally low in calcium (for example, 0.03 per cent calcium compared to 0.26 per cent phosphorus), and there may not be a natural source such as clover, weeds, leafy stubble or edible bush in the paddock.

The safestt and most effective calcium supplement is finely ground limestone added to the feed, but some farmers have used other sources of calcium such as gypsum and superphosphate in this manner.

The Sandplain Lupin : Its Nutritional Value And Grazing Management, P W. Morcombe

Journal of the Department of Agriculture, Western Australia, Series 4

The sandplain lupin or Western Australian blue lupin (Lupinus cosentinii) was introduced to the West Midlands at the turn of the last century. Since that time it has been used as a self-regenerating summer forage for sheep and cattle.

Being deep rooted, it has adapted well to the sandy soils from Perth to Northampton, and plantings now cover more than 100,000 ha.

As few other improved pasture species will persist on these deep sands the sandplain lupin provides an important source of summer feed for grazing livestock. A stand can be grazed throughout summer at stocking rates of 10 to …

Weighing Scales For Sheep Do Pay, W D. Roberts

Journal of the Department of Agriculture, Western Australia, Series 4

Sheep producers can improve production by using weighing scales and keeping accurate records of weights.

Withiut some objective measurement, such as weighing, producers have no accurate method of identifying the heaviest, lightest and average weight of a group of sheep.

They could try to esstimate weight by eye - but most people are poor judges of body weight.

Evaluation Of The Crack Approach For The Control Of Drench Resistance In Sheep Worms, J R. Edwards, Helen Chapman, Jon Dunsmore

Journal of the Department of Agriculture, Western Australia, Series 4

The Department of Agriculture launched the CRACK approach to worm control in September 1985 in response to finding that anthelmintic (drench) resistant worms were present on 68 per cent of a random selection of Western Australian sheep farms.

The high cost of internal parasites in terms of lost production and drench costs, together with the high prevalence of resistant worms of farms, confirmed that changes were needed to existing parasite control measures in sheep.l

Herd Improvement Service Forges Ahead, M P. Bond

Journal of the Department of Agriculture, Western Australia, Series 4

Since its establishment three years ago, the Herd Improvement Service has steadily expanded the range of services provided to Western Australian livestock producers. The genetic advancement and improved hers management offered by the service give farmers the ability to use modern technology in the most cost-effective way. There is an increasing realisation amongst farmers that to survive and remain competitive, it is worthwhile to invest in such technology.

The Herd Improvement Service is a statutory corporation which was formed to improve the productivity of the State's livestock enterprises. Most of the organisation's activities have been directed to servicing the dairy …

Survival Of Lambs, R W. Kelly, David Lindsay

Journal of the Department of Agriculture, Western Australia, Series 4

Between one in every five or six lambs that are born each year in Western Australia die at or about the time of birth. This represents a loss approaching two million lambs and is arguably out single greatest wastage in sheep production. The deaths have an immediate impact on lambing performance and therefore lamb sales, and ultimately effects on such areas as selection of breeding replacement stock, the proportion of ewes and weathers that can be run in a self-replacing flock and the amount of wool produced and its uality.

This article summarises information on what influences lamb survival, and …

Reproductive Wastage In Sheep, R W. Kelly

Journal of the Department of Agriculture, Western Australia, Series 4

The average lambing performance of Western Australia's ewe flock fluctuates between 60 and 70 per cent. Although this level of performance and variation between years is important for the sheep industry, individual farmers are more concerned about performance of their own flocks.

Figure shows the range in lambing performances that exist between farms in this State in 1983-84. The seriously poor performance of many flocks is apparentm - 28 percent of farms had less than 60 per cent lambing. By contrast, 24 farms had performances better than 100 per cent. The reasons for the large differences between farms ( and …

Ovulation Rate Of Ewes : Role Of Energy And Protein, E Teleni, J. B. Rowe

Journal of the Department of Agriculture, Western Australia, Series 4

Western Australia's sheep farmers are familiar with the low ovulation rate of Merino ewes and how this limits the lambing performance of ewe flocks.

One way in which ovulation rate and therefore lambing percentage may be increased is to feed seed of sweet lupin (Lupinus augustifolius) to ewes at mating. However, Department of Agriculture research has found that these increases do not show up consistently, and that there is considerable variability between farms.

If improved nutrition is to be a useful way to increasing ovulation rate, the mechanism by which nutrition affects ovulation rate must first be understood. This article …

Pregnancy Diagnosis Using Ultrasound, M A C Johns

Journal of the Department of Agriculture, Western Australia, Series 4

Few Western Australian ewe flocks are diagnosed for pregnancy despite the precence of high numbers of barren ewes. Surveys of farm flocks in the early 1970s recorded that between 14 and 29 per cent of ewes failed to lamb each year.

Techniques for diagnosing pregnant ewes have been available for many years, but ultrasonic devices and computer technology have made it possible for skilled operators to determine whether ewes are pregnant and more importantly, whether they have one, two or more foetuses.

Once the number of pregnant ewes is known farmers can use labour more efficiently. They can minimise the …

Atrophic Rhinitis In Pigs, A R. Mercy

Journal of the Department of Agriculture, Western Australia, Series 4

Severe atrophic rhinitis in pigs recurred recently in Australia after an apparent absence of some 20 years. The first of these recent cases occurred in a Westerm Australian herd in late 1984 and since then six other local herds have reported the disease. Severe atrophic rhinitis has also been seen recently in South Australia.

Atrophic rhinitis is a complex disease which causes degeneration of the nasal cavity, twisting of the snout and sometimes occasional bleeding from the nose.

It occurs only in pigs and severely affected animals may have a slower growth rate.

A Survey Of Drench Resistance In Sheep Worms, J R. Edwards, R. Wroth, G. C. De Chaneet, R. B. Besier, J. Karlsson, P. W. Morcombe, D. Roberts, G. Dalton-Morgan

Journal of the Department of Agriculture, Western Australia, Series 4

Sheep worms which are resistant to chemical drenches have been detected with increasing freuency is Western Australia's south-western farming areas between 977 and 1980. These worms have anthelmintic resistance and such genetis resistance puts essential internal parasite control practices at risk.

This prompted veterinarians in the Esperance, Albany, Bunbury, Geraldton and Northam areas to survey farms to determine the prevalence of resistance to drenches and to define those sheep management practices which encourage its development.

This article describes the survey which was conducted to assess the extent of drench resistance, what causes its build-up and how it can be controlled …

'Dermo' Fleece Rot And Body Strike On Sheep, S G. Gherardi, S. S. Sutherland, N. Monzu

Journal of the Department of Agriculture, Western Australia, Series 4

Blowfly strike is one of the major problems confronting the sheep industry in Austrsalia, with an estimated totsalcost of control eceeding $100 million each year.

Sheep are susceptible to five types of strike: body, breach, poll, pizzle and wound. Body strike, is of greater economic importance because its sporadic occurence from year to year makes it difficult to predict and cintrol. Outbreaks of body strike after rain can affect large numbers of sheep and inflict severe production losses.

In eastern Australia fleece rot is generally considered to be the main predisposing factor to blowfly strike, but in Western Australia evidence …

Dispelling Some Myths About 'Dermo', J R. Edwards

Journal of the Department of Agriculture, Western Australia, Series 4

There are a lot of misconceptions and myths about dermatophilosis, a disease which can kill young lambs, affect wool quality, make shearing difficult and make sheep susceptible to fly strike.

One misconception is perpetuated by the incorrect use of the name mycotic dermatitis, which implies that a fungus causes the disease. This is not so.

The disease is caused by the bacteria Dermatophilus congolensis, which attacks the sheep's skin and eventually forms a lesion or scab in the wool, and so is better called dermatophilosis, 'dermo' or 'lumpy wool'.

Veterinary Epidemiologist at the Albany Regional Office, J.R. Edwards, discusses …

New Developments In Footrot Control, R B. Richards, L. J. Depiazzi, R. V. R. Gwynn

Journal of the Department of Agriculture, Western Australia, Series 4

The eradication policy for footrot in sheep adopted by the Western Australian Department of Agriculture has produced an overall decline in the number of properties with the disease.

Our knowledge of the disease has improved substantially as a result of the research conducted at the Slabany Regional Veterinary Laboratory in recent years. Laboratory tests now sssist stock inspectors and veterinary officers to distinguish between different forms of footrot and to quarantine and eradicate accordingly.

The recent discovery of more effective foot-bathing solutions by officers of the Victorian Department of Agriculture will greatly assist further eradication procedures.

Western Australia's sheep industry …

Protecting Off-Shears Sheep In Adverse Weather, T M. Ellis

Journal of the Department of Agriculture, Western Australia, Series 4

In January 2982 in the Narrogin-Darkan area of Western Australia, about 14,500 sheep up to 40 days off-shears died after a 48-hour period of heavy soaking rain that followed a thunderstorm three days previously. An estimated 100,000 sheep died throughout the South-West at the time.

P. G. Buckman - at the time Department of Agriculture District Veterinary Officer, Narrogin - surveyed 17 properties in the area. He found that losses in unshedded sheep 0 to 40 days off-shears ranged from 0 to 84 per cent of sheep on the property with an overall average of 27.9 per cent. Rainfall in …

Worms In Cattle In Western Australia's South West, G C De Chaneet

Journal of the Department of Agriculture, Western Australia, Series 4

In the early 1970s, when beef cattle numbers increased in the South West, worms came to be recognised as the cause of one of the most significant health problems affecting production. The disease ostertagiosis, caused by the brown stomach worm, Ostertagia ostertagi, started to occur regularly, but the anthelmintics available at the time were limited in their efficiency against the parasite. Because little was known of the epidemiology of ostertagiosis under local conditions, recommendations for control were based on observations made elsewhere in Australia and overseas. These were unsuited to local conditions and did not provide adequate control.

Argt Caused By Toxic Antibiodies : Research Report, P Vogel

Journal of the Department of Agriculture, Western Australia, Series 4

A fortunate coincidence, discovered recently, has provided annual ryegrass toxicity researchers with valuable knowledge which may help them understand how the ARGT toxins affect animals, and further their investigations into vaccine development. A toxic antibiotic, identified years ago, has proved to be closely related to the ARGT toxins. Antibiotics are generally regarded as effective agents for the control of many bacterial and fungal infections. However, some of them are toxic to both the bacteria and the host, whether man or animal.

Testing Bulls For Breeding Soundness, R L. Peet

Journal of the Department of Agriculture, Western Australia, Series 4

New tests are available to ensure that bulls are fertile.